# Programs used for graphics and tables of the book:
#    "Data anlysis and data mining" by A.Azzalini and B.Scarpa,
#     © Oxford University Press, 2012 (ISBN 978-0-19-976710-6).
#
# Code regarding section 4.2 (© 2003, 2004, 2012 A.Azzalini and B.Scarpa)
#------------------------------------------------------------------------
source("base-www.R")
library(sm)
library(kknn)
#
auto <- read.table("../data/auto.dat", header=TRUE)


fit0 = loess(city.distance~engine.size,data=auto)
pred0 = predict(fit0,auto)
RSS0 = sum((auto$city.distance-pred0)^2)
fit = loess(city.distance~engine.size+curb.weight,data=auto)
pred = predict(fit,auto)
RSS = sum((auto$city.distance-pred)^2)
anova(fit0,fit)

fit.lm0 = lm(city.distance~engine.size,data=auto)
fit.lm = lm(city.distance~engine.size+curb.weight,data=auto)
anova(fit.lm0,fit.lm)